media player responds slow, plays slow

  Hi,
I've just installed a new hard drive and re-installed xp, sp2 and a few
other programs.
When I've come to play a video on media player 10 (with is updated/patched
via ms update) it plays/responds ver slow.  The playback is staggered and
jerky and the sound is out of sync etc.  The player responds slow as well and
freezes windows when I close it for about 10 seconds.
I have 2gb of RAM, so that can't be it ? p4 2.8, and the video ran fine on
the other installation of xp I had.

Could it be the hard drive ?  everything else seems to run to speed so far?
so its unlikely....

Any idea on how to rectify much appreciated.